Bovine fascioliasis in Brazil: Economic impact and forecasting

Fasciola hepatica causes liver damage and poor growth in cattle and other animals, including humans. Although the disease occurs throughout the country, it is hyperendemic in cattle in the South of Brazil. This work aimed to determine the economical loss by carcass weight variance using data from all the states where F. hepatica is found, as well as to run a disease forecast analysis for the Rio Grande do Sul State. We found a direct loss of approximately US$ 210 million/year from infected cattle in Brazil and the ARIMA model analysis revealed that an increase of fascioliasis is most probable if no parasite control program is adopted.

Decrease in tick bite consultations and stabilization of early Lyme borreliosis in the Netherlands in 2014 after 15 years of continuous increase

BACKGROUND

Nationwide surveys have shown a threefold increase in general practitioner (GP) consultations for tick bites and early Lyme borreliosis from 1994 to 2009 in the Netherlands. We now report an update on 2014, with identical methods as for the preceding GP surveys.

METHODS

To all GPs in the Netherlands, a postal questionnaire was sent inquiring about the number of consultations for tick bites and erythema migrans diagnoses (most common manifestation of early Lyme borreliosis) in 2014, and the size of their practice populations.

RESULTS

Contrasting to the previously rising incidence of consultations for tick bites between 1994 and 2009, the incidence decreased in 2014 to 488 consultations for tick bites per 100,000 inhabitants, i.e., 82,000 patients nationwide. This survey revealed a first sign of stabilization of the previously rising trend in GP diagnosed erythema migrans, with 140 diagnoses per 100,000 inhabitants of the Netherlands. This equals about 23,500 annual diagnoses of erythema migrans nationwide in 2014.

CONCLUSIONS

In contrast to the constantly rising incidence of GP consultations for tick bites and erythema migrans diagnoses in the Netherlands between 1994 and 2009, the current survey of 2014 showed a first sign of stabilization of erythema migrans diagnoses and a decreased incidence for tick bite consultations.

Physician reported incidence of early and late Lyme borreliosis

Background

Lyme borreliosis is the most common vector-borne disease in Europe and North America. The objective of this study is to estimate the incidence of tick bites and Lyme borreliosis, representative of our entire country, including erythema migrans, disseminated Lyme borreliosis and persisting symptoms attributed to Lyme borreliosis.

Methods

A questionnaire on clinical diagnoses of Lyme borreliosis was sent to all GPs, company physicians, and medical specialists. To adjust for possible misclassification and telescoping bias, we sent additional questionnaires to categorize reported cases according to likelihood of the diagnosis and to exclude cases diagnosed outside the target period.

Results

Adjusted annual incidence rate for disseminated Lyme borreliosis was 7.7 GP reports per 100,000 inhabitants, and for persisting symptoms attributed to Lyme borreliosis was 5.5 GP reports per 100,000 inhabitants, i.e. approximately 1,300 and 900 cases respectively. GP consultations for tick bites and erythema migrans diagnoses were 495 and 132 per 100,000 inhabitants, respectively, i.e. 82,000 and 22,000 cases in 2010.

Conclusions

This is the first reported nationwide physician survey on the incidence of tick bites and the whole range of manifestations of Lyme borreliosis, including persisting symptoms attributed to Lyme borreliosis. This is crucial for complete assessment of the public health impact of Lyme borreliosis.

Electronic supplementary material

The online version of this article (doi:10.1186/s13071-015-0777-6) contains supplementary material, which is available to authorized users.

The use of bulk-tank milk ELISAs to assess the spatial distribution of Fasciola hepatica, Ostertagia ostertagi and Dictyocaulus viviparus in dairy cattle in Flanders (Belgium)

Fasciola hepatica, Ostertagia ostertagi and Dictyocaulus viviparus are helminth parasites with a wide distribution and an important economic impact in cattle in temperate climates. This paper describes the spatial distribution of F. hepatica, O. ostertagi and D. viviparus in dairy herds in Flanders (Belgium). One thousand eight hundred herds were selected at random from the Flemish dairy population (n=7002), stratified on community level to obtain a sample representative for the entire study area. From each herd, a bulk milk sample collected in autumn 2006 was analysed with previously described antibody-ELISAs in order to identify herds where the parasite infection level is likely to cause production loss (F. hepatica and O. ostertagi) (defined as economic infections) or where patent infections have been present over the past grazing season (D. viviparus). The herd prevalence of economic infections with F. hepatica and O. ostertagi was 37.3% (95% Confidence Interval (CI): 35.1-39.7) and 59.1% (95%CI: 56.8-61.4), respectively. The herd prevalence of D. viviparus was 19.6% (95%CI: 17.7-21.6). On 28.9% (CI 26.8-31.3) of the herds, low levels of infection were observed for all three of the helminths. The presence of clustering of (economic) infections was studied using Moran's I, whereas the location and size of the clusters were studied using the spatial scan statistic, the Local Indicator of Spatial Association and Kernel density plotting. A marked clustering in the spatial distribution of F. hepatica and a mild clustering in the spatial distribution of O. ostertagi were observed. D. viviparus infections were spread evenly over Flanders. Knowledge of locations of high risk areas can lead to increased awareness and may be the start of the development of regionally adapted control measures.